• "Game of Thrones" actor Hafþór "Thor" Björnsson is 6'9", and weighs 400 pounds.
• In a new Instagram post, he's seen holding a mug that looks extremely small in his hands.
• People can't get enough of how the cup practically looks like a shot glass when he holds it.

Hafþór "Thor" Björnsson is the 30-year-old Icelandic actor who plays Gregor "The Mountain" Clegane on "Game of Thrones." His character's legendary stature is matched by the real-life man, who stands at 6'9" and weighs approximately 400 pounds. 

Read more:  Björnsson crowned the World's Strongest Man in 2018

Now people cannot get enough of a photo shared of Björnsson holding a regular coffee mug that looks positively tiny in his hands.

On Friday morning, Björnsson posted a photo on Instagram of him and his wife, Kelsey Henson, holding what appears to be mugs of hot chocolate with whipped cream on top. While Henson's cup appears pretty normal (if maybe a bit on the small side), the mug in Björnsson's hand looks like an optical illusion. 

Read more: 16 photos of The Mountain from 'Game of Thrones' and his wife, Kelsey Henson — who have a height difference of 19 inches

The picture was shared to the "Absolute Units" subreddit where over 40,000 people upvoted the image in one day. 

"It looks like he can take that hot chocolate down like a shot," the top comment from Redditor Redheadkai says.

His Instagram post was bombarded with comments from fans who can't believe the mug looks effectively like a shot glass or a cup from a dollhouse tea set.

"That mug looks like a thimble in your massive paw," one person wrote.

"Thought that was a miniature mug until I saw the mug your other half is holding lol," another said.

The "Game of Thrones" star is no stranger to people reacting strongly to his size online. Photos of him and his wife (who is 19 inches shorter than him) have gone viral, similar to a memorable photo of basketball legend Shaquille O'Neal and his ex-girlfriend Nikki "Hoopz" Alexander.

Björnsson will appear on the coming eighth and final season of "Game of Thrones," which premieres Sunday, April 14 on HBO.

• Read more:
• 16 photos of Bjornsson and his wife, Kelsey Henson — who have a height difference of 19 inches
• The 400-pound actor who plays 'The Mountain' on 'Game of Thrones' eats 10,000 calories a day
• KFC's newest Colonel Sanders is The Mountain from 'Game of Thrones'
• 'Game of Thrones' star Thor Bjornsson teased a new season 8 scene — and fans are hoping this confirms an epic theory
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